[coolspot]

Impressive:

> Ghost is a single-rotor aircraft. The mechanicals of the rotor system are harder to design and manufacture than a DJI-style quadcopter, and flight controls are harder to program, but the result is much lower aerodynamic disk loading that results in longer endurance (over 100 minutes with real mission payloads), near-silent acoustic signature, high max payload capacity (dozens of pounds), and high speed. Compare this with a DJI Inspire 2, a high-end offering that costs $3000 that can lumber around with a couple pounds for 24 to 27 minutes, props screaming.

> Ghost is autonomous, powered by an onboard AI Core that can perform 32 trillion operations per second.

[baybal2]

Single rotor controls are much, much simpler.

At least it does not require a mandatory PID control to not fall out of the sky.

Very little math involved in control of a helicopter. A 3 actuator type with 1 actuator for each axis basically has no need for any control signal manipulation, and can be made fully analog.

And a helicopter can be made more or less statically stable by pure mechanics, and aerodynamics.

P.S.

It doesn't seem that the drone in question exist in anything, but CGI at the moment.

P.P.S.

And quite unsound CG at that. On some of their CG shots, a swashplate actuators are attached with their axis coincidal with that rotor..., and a tail rotor control yoke not attached to anything...

[coolspot]

In my understanding Ghost 1-3 do exist, but classified.

Ghost 4 is in development/entering production. Being military project, it is likely that publishing real photos would be difficult at this stage for various reasons. Same with giving real blueprints/CAD files to a 3D artist for marketing materials.

[CamperBob2]

Given this, what are some reasons why single-rotor RC aircraft have never been as popular as quads?

[rasz]

RC Heli = expensive specialized mechanical parts, collective pitch Rotor Head is a nightmare.

quad = difficult to develop software control loop

One is easier to replicate after initial development than the other. Heli crash also usually results in destruction of Rotor Head, the most expensive part. You could use an analogy of Carburetor versus EFI.

[baybal2]

Single rotor crafts do not avail for plasticky parts, and require more non-off-the shelf parts in general.

Even very first quads were for example easily makeable with existing toy parts, and plastic.

But with just a bit more efforts, single rotor craft take a lead from quads by a significant margin.

[CamperBob2]

Interesting, thanks. I've never heard this perspective before. So you'd say that anyone building an elaborate homebrew quad -- e.g., the TechIngredients guy at https://www.youtube.com/watch?v=4ZPvZiJLbvI , who generally seems to know what he's doing -- would be better off putting comparable effort (and comparable cash) into a single-rotor aircraft instead?